Garden sprayers are very handy for distributing pesticides, fertilizers and weed killers around your home and garden. As such, anyone might think that a sprayer is just like any other sprayer, and if it works well enough for one type of application, it will work well for any application. To that end, you can use a garden sprayer for painting, but there are certain considerations you must understand before you attempt it.
Most latex paints are water-based and thick and need to be heavily diluted before you can spray them.
Mix one part paint to 3 parts water in your sprayer.
Swirl and gently shake the mixture.
Pump up your garden sprayer.
Spray on as fine a mist as possible without the sprayer nozzle clogging up. Adjust the nozzle as needed to prevent clogging.
You will need to spray on 4 sprayer coats to achieve the consistency of one brush coat of non-diluted paint. This works best on horizontal surfaces as vertical surfaces are prone to dripping and running with this type of dilution requirement.
Oil-based paint and stains need to be diluted in a 50/50 mix inside the sprayer.
Swirl the mix around, and pump it up.
Spray on as fine a mist as possible without the nozzle clogging up. Adjust as needed.
You will need to spray two coats of oil-based paint or stain to make one regular coat.